My Owon SDS 7102 was completely dead when switching on yesterday - both on AC and with the integrated battery. After a short investigation, I found that the battery didn't delivery any voltage, and the device uses only the two outmost pins of the battery pack. I could charge the battery externally - the beginning voltage of a bit over 6 volts confirmed that the battery was empty. After charging it with 6 Ah (the designed capacity was 8 Ah, and I played safe here) I but it back into the device - and it worked again! Both via only battery and with battery+AC. In the later case the led is orange (normal for charging), and the fan is a very tiny bit louder, so also the AC part seems to be fine.
Or should I suspect a further problem?